Physical unclonable function device and operation method thereof, and electronic device

Abstract

Provided are a physical unclonable function device and an operation method thereof, and an electronic device. The device includes: a first signal generating circuit configured to generate a first clock signal of n-th period according to a control signal of the n-th period and an input signal of the n-th period; a second signal generating circuit configured to generate a second clock signal of the n-th period according to the control signal of the n-th period and the input signal of the n-th period; an output circuit configured to output an output signal of the n-th period according to the first and second clock signal of the n-th period; and a control circuit configured to process an initial control signal of the n-th period to obtain the control signal of the n-th period according to a reference value comprising a logic level of an output signal of (n−1)-th period.

What is claimed is: 
     
       1. A physical unclonable function device, comprising:
 a first signal generating circuit configured to generate a first clock signal of n-th period according to a control signal of the n-th period and an input signal of the n-th period, where n is an integer greater than or equal to 2; 
 a second signal generating circuit configured to generate a second clock signal of the n-th period according to the control signal of the n-th period and the input signal of the n-th period; 
 an output circuit configured to output an output signal of the n-th period according to the first clock signal of the n-th period and the second clock signal of the n-th period; and 
 a control circuit configured to process an initial control signal of the n-th period to obtain the control signal of the n-th period according to a reference value, the reference value comprising a logic level of an output signal of (n−1)-th period, 
 wherein a probability that the logic level of the output signal is a first logic level is 0.5, a probability that the logic level of the output signal is a second logic level is 0.5, and the first logic level and the second logic level have opposite logics. 
 
     
     
       2. The physically unclonable functional device according to  claim 1 , wherein:
 the first signal generating circuit comprises a first time-average-frequency direct period synthesis (TAF-DPS) circuit, and the second signal generating circuit comprises a second TAF-DPS circuit; and 
 the control signal comprises a control word, and the initial control signal comprises an initial control word. 
 
     
     
       3. The physically unclonable functional device according to  claim 2 , wherein:
 the initial control word is C=F+r, where F is an integer, and r is a decimal greater than 0 and smaller than 1; and 
 the control word of the n-th period is C(n) which is obtained by performing a mathematical operation on the reference value and at least one of F or r. 
 
     
     
       4. The physically unclonable function device according to  claim 3 , wherein each of the first clock signal and the second clock signal has a first period with a probability of r and a second period with a probability of 1−r, the first period is F+1, and the second period is F. 
     
     
       5. The physical unclonable function device according to  claim 3 , wherein C(n)=M+N, where M is one of F and r, and N is obtained by performing the mathematical operation on the reference value and the other of F and r. 
     
     
       6. The physical unclonable function device according to  claim 5 , wherein M is F, and N is obtained by performing the mathematical operation on the reference value and r. 
     
     
       7. The physically unclonable function device according to  claim 6 , wherein the mathematical operation comprises a multiplication operation. 
     
     
       8. The physically unclonable functional device according to  claim 7 , wherein:
 N=Σ i=1   m B └A(n-i)┘ ·r i , where m is a number of digits of r after decimal point, ri=0·p, p is the last i digits in r, and B └A(n-i)┘  represents a logic level of an output signal of (n−i)-th period; and 
 in a case where n-i is smaller than or equal to 0, B └A(n-i)┘ =0. 
 
     
     
       9. The physical unclonable function device according to  claim 3 , wherein r=0.5. 
     
     
       10. The physical unclonable function device according to  claim 2 , wherein each of the first TAF-DPS circuit and the second TAF-DPS circuit is configured to determine the input signal of the n-th period according to the control word of the n-th period. 
     
     
       11. The physically unclonable functional device according to  claim 10 , further comprising:
 a ring oscillator configured to generate K clock signals with a same frequency, wherein there is a same time interval between j-th clock signal and (j−1)-th clock signal, where K is an integer greater than or equal to 2, and j is any integer between 2 and K; 
 the first TAF-DPS circuit comprising: 
 a first accumulator configured to calculate an accumulated value A1(n) of the n-th period in the first accumulator according to following formula: A1(n)=(A1(n−1)+C(n))(mod K), where A1(n−1) is an accumulated value of (n−1)-th period in the first accumulator, C(n) is the control word of the n-th period, and C(n) is greater than or equal to 2 and smaller than or equal to 2K−1, 
 a first multiplexer, and 
 a first register configured to control the first multiplexer to select one of the K clock signals as the input signal of the n-th period according to an integer in A1(n); and 
 the second TAF-DPS circuit comprising: 
 a second accumulator configured to calculate an accumulated value A2(n) of the n-th period in the second accumulator according to following formula: A2(n)=(A2(n−1)+C(n))(modK), where A2(n−1) is an accumulated value of the (n−1)-th period in the second accumulator, A2(1)=A1(1), and A2(n)=A1(n), 
 a second multiplexer, and 
 a second register configured to control the second multiplexer to select the one of the K clock signals as the input signal of the n-th period according to an integer in A2(n), 
 wherein there are positive integers q1 and f1 such that A1(q2) is constantly equal to A1(f2)(mod K), where f1 is greater than q1, and 
 wherein there are positive integers q2 and f2 such that A2(q2) is constantly equal to A2(f2)(mod K), where f2 is greater than q2. 
 
     
     
       12. The physical unclonable function device according to  claim 11 , wherein A2(1)=A1(1), A2(n)=A1(n), f1=q1, and f2=q2. 
     
     
       13. The physically unclonable functional device according to  claim 12 , wherein:
 the control circuit is further configured to provide an initial value; and 
 the first register and the second register are further configured to control the first multiplexer and the second multiplexer, respectively, to select a same one of the K clock signals as an input signal of the first period according to the initial value. 
 
     
     
       14. The physical unclonable function device according to  claim 1 , wherein:
 the first signal generating circuit is further configured to generate a first clock signal of a first period according to a control signal of the first period and an input signal of the first period; 
 the second signal generating circuit is further configured to generate a second clock signal of the first period according to the control signal of the first period and the input signal of the first period; and 
 the output circuit is further configured to output an output signal of the first period according to the first clock signal of the first period and the second clock signal of the first period. 
 
     
     
       15. The physical unclonable function device according to  claim 1 , wherein:
 c-th rising edge of the first clock signal reaches the output circuit at a first time, and c-th rising edge of the second clock signal reaches the output circuit at a second time, where c is an integer greater than or equal to 1; and 
 the output circuit is configured to determine a logic level of the output signal of the n-th period according to at least the first time and the second time. 
 
     
     
       16. The physically unclonable functional device according to  claim 15 , wherein:
 (c+1)-th rising edge of the first clock signal reaches the output circuit at a third time, and (c+1)-th rising edge of the second clock signal reaches the output circuit at a fourth time; and 
 the output circuit is configured to determine the logic level of the output signal of the n-th period according to a first difference between the third time and the first time, and a second difference between the fourth time and the second time. 
 
     
     
       17. The physically unclonable functional device according to  claim 16 , wherein:
 in a case where the first difference value is greater than or equal to the second difference value, the logic level of the output signal of the n-th period is 1; and 
 in a case where the first difference value is smaller than the second difference value, the logic level of the output signal of the n-th period is 0. 
 
     
     
       18. An electronic device, comprising the physical unclonable function device according to  claim 1 . 
     
     
       19. A physical unclonable function device, comprising:
 a first signal generating circuit configured to generate a first clock signal of n-th period according to a control signal of the n-th period and an input signal of the n-th period, where n is an integer greater than or equal to 2; 
 a second signal generating circuit configured to generate a second clock signal of the n-th period according to the control signal of the n-th period and the input signal of the n-th period; 
 an output circuit configured to output an output signal of the n-th period according to the first clock signal of the n-th period and the second clock signal of the n-th period; and 
 a control circuit configured to process an initial control signal of the n-th period to obtain the control signal of the n-th period according to a reference value, the reference value comprising a logic level of an output signal of (n−1)-th period, wherein: 
 the first signal generating circuit comprises a first time-average-frequency direct period synthesis (TAF-DPS) circuit, and the second signal generating circuit comprises a second TAF-DPS circuit; and 
 the control signal comprises a control word, and the initial control signal comprises an initial control word, wherein the initial control word is C=F+r, where F is an integer, and r is a decimal greater than 0 and smaller than 1, and the control word of the n-th period is C(n) which is obtained by performing a mathematical operation on the reference value and at least one of F or r. 
 
     
     
       20. A physical unclonable function device, comprising:
 a first signal generating circuit configured to generate a first clock signal of n-th period according to a control signal of the n-th period and an input signal of the n-th period, where n is an integer greater than or equal to 2; 
 a second signal generating circuit configured to generate a second clock signal of the n-th period according to the control signal of the n-th period and the input signal of the n-th period; 
 an output circuit configured to output an output signal of the n-th period according to the first clock signal of the n-th period and the second clock signal of the n-th period; and 
 a control circuit configured to process an initial control signal of the n-th period to obtain the control signal of the n-th period according to a reference value, the reference value comprising a logic level of an output signal of (n−1)-th period, wherein: 
 c-th rising edge of the first clock signal reaches the output circuit at a first time, and c-th rising edge of the second clock signal reaches the output circuit at a second time, where c is an integer greater than or equal to 1, and 
 the output circuit is configured to determine a logic level of the output signal of the n-th period according to at least the first time and the second time.